Abstract: The intensifying water shortage in Algeria makes clear the need of novel, sustainable strategies to protect distribution networks. Current infrastructure struggles with frequent failures, particularly leaks stemming from corrosion or handling damage during transport and installation. High-density polyethylene (HDPE) has become a material of choice because it handles these challenges well; it is cost-efficient, flexible, and tough enough to withstand harsh environments.This work investigates the failure risks of HDPE pipelines manufactured by ITP Alg{é}rie -- Innovation Transformation Polym{è}re. Mechanical tests were performed on HDPE 100 to determine its fundamental properties, including burst tests under internal pressure and load/unload experiments aimed at establishing a material-specific damage law revealed the dominant degradation mechanisms that occur under different operational and environmental conditions. Based on these findings, a predictive numerical model was developed to simulate damage progression and anticipate potential failures in service. This study introduces a unique hybrid composite patch designed for the precise rehabilitation of compromised pipeline sections. It shows strong promise for rebuilding the mechanical integrity of pipes, which is vital for maintaining a safe and long-lasting drinking water supply.